VS2010 source location problem.

[lucky6969b]

Firstly, I created a global environment variable OGRE_HOME=E:\ogre_source\OGRE
I unzipped a zip file into E:\ogre_source\OGRE\pathfinding

E:\
   ogre_source
                OGRE
                      pathfinding
                                  bin
                                  src 
                                  samples
                                             src << here

Then, I have a path for the source specified in the "source folder" of the project in the project properties section,
$(OGRE_HOME)\pathfinding\samples

Inside this folder I have src folder in which contains a .cpp file
The file is hard-coded with path src\OgrerecastApplication.cpp

But the VS2010 compiler still cannot find this file. I wonder what other settings are involved?
Thanks
Jack